1. Field
This disclosure relates to a method for fabricating a carbon material, a carbon material obtained thereby, and a cell material and device using the same.
2. Description of the Related Art
Carbon materials are valuable in use and are widely used in a broad range of industrial fields, including catalyst supports, electrode materials for fuel cells or secondary batteries, hydrogen storage materials, super capacitors, composite materials, solar cells and various electronic devices.
Among such carbon materials, carbon fibers or carbon tubes have received attention. Carbon fibers or carbon tubes have been studied in the fields of electrode materials for fuel cells and secondary batteries, since they have a high conductivity and large specific surface area.
Branches in the form of carbon fibers or carbon tubes (hereinafter referred to “branches”) may be grown from stem carbon fibers or stem carbon tubes. Carbon fibers or carbon tubes which have the stem portion and branch portion may be referred to branched carbon fibers or branched carbon tubes.
Branched carbon fibers or branched carbon tubes may have a large specific surface area compared to carbon fibers or carbon tubes without branches due to a large number of branches.
Therefore, the branched carbon fibers or branched carbon tubes may allow metal catalyst particles to be highly supported thereon and dispersed therein. This feature of the branched carbon fibers or branched carbon tubes may be applied to the industrial fields requiring a large specific surface area, such as in the fields of catalyst supports, secondary batteries, hydrogen storage materials, capacitors such as super capacitors, composite materials, solar cells, and various electronic devices.
Methods for fabricating carbon fibers or carbon tubes may include an arc discharge process, laser ablation process, chemical vapor deposition process, etc.
For example, metal catalyst particles may be dispersed highly in silicon single crystals, silica, aluminum oxide, etc., and then carbon sources may be allowed to flow therethrough in a vapor phase so that stem carbon fibers or carbon tubes are grown.
Methods for fabricating branched carbon fibers or branched carbon tubes may be similar to the above-mentioned methods for growing stem carbon fibers or stem carbon tubes.
For example, metal catalyst particles may be dispersed on the surface of stem carbon fibers or stem carbon tubes, and then hydrocarbons functioning as carbon sources for growing branches may be injected thereto so that branches can be grown from the stem carbon fibers or stem carbon tubes at high temperature.